Lateral side channel fuel pumps are know, as illustrated in U.S. patent to Scheinfurther No. 4,408,952 issued Oct. 11, 1983. Regenerative turbine type fuel pumps are known as illustrated in U.S. Pat. No. 4,556,363 to Watanabe et al, issued Dec. 3, 1985. Two stage fuel pumps combining a lateral side channel pump as a first stage and a regenerative turbine pump as a second stage are known, as illustrated in British Patent GB 2,134,598 published Aug. 15, 1984 and in a U.S. Pat. No. 4,408,952 to Schweinfurter.
A pump with a lateral side channel as a first stage and a positive displacement gear rotor as a second stage is disclosed in U.S. Pat. No. 5,149,252 issued Sep. 22, 1992 by Charles H. Tuckey and assigned to the assignee of the present application.
Two stage pumps utilizing a single rotor are illustrated in the above referenced British Patent 2,134,598 and U.S. Pat. 4,408,952, and the concept of vapor release, sometimes referred to as de-gassing is disclosed also in these patents as well as in U.S. Pat. No. 4,149,252.
Thus, two stage fuel pumps utilizing a single rotor, combining a lateral side channel pump and a regenerative turbine pump, and also incorporating vapor release, are illustrated in the above referenced patents. The present invention is directed to a two stage pump with a lateral side channel and a regenerative turbine with a single rotor and a housing which is designed to effectively increase vapor separation and release as well as the efficiency of the combined pumping stages.